Indoor Air Quality Assessments: Mould Daniel Fong

National Collaborating Centre for Environmental Health Indoor air quality workshop

CIPHI National Education Conference Winnipeg, MB | June 23, 2013

Outline

• What is Mould? • Sources • Health effects

Introduction

• Sampling methods • Interpreting results (example lab reports)

Sampling and Interpretation

• Education • Remediation - see resources

Management

Introduction

What is Mould? • Moulds are multi-cellular spore-forming filamentous organisms

– Ubiquitous, outdoor and indoor – >100,000 reported species, few hundred are relevant to human

exposure – Saprophytes (live off dead organic matter),

parasites, symbionts

• Growth requires… – O2 – Organic carbon source – Temperature (ideal = 18-32°C) – Time – Moisture (e.g., RH >60%)

• most important and only factor that can be controlled indoor

Kathie Hodge http://www.flickr.com/photos/cornellfungi/5613739709/

Sources

• Walls, floors and ceilings, wallpaper

• Insulation, carpet, • Furniture, mattress • Paper, cardboard • Food, oil • HVAC

• Dust • Plants • Soil • Other biodegradable organic

materials, even in small amounts or parts of seemingly inorganic substances (e.g., residue/condensation on glass, plastics, caulking)

Concentrations are generally higher outdoor vs. indoor

Health Effects • Irritation

– Eyes, skin – Upper RT

• Nose, throat irritation – Lower RT

• Cough, wheezing, shortness of breath

• Infection (opportunistic)

• Immunological reactions – Asthma symptoms – Hypersensitivity pneumonitis

(inflammation of alveoli) – Allergic rhinitis, sinusitis,

dermatitis

Vulnerable populations: immunocompromised (HIV/AIDS), immunosuppressed

(transplant, chemotherapy patient); those with allergies, chronic underlying respiratory disease

(COPD, asthma); infants, elderly

Sampling & Interpretation

Many factors affecting the composition of mould in the air…

• Growth + distribution • Note outdoor and indoor conditions • A few examples…

– Climate • temperature, season, time of day,

– Aerosolization • Wind, rain, anthropogenic activity, turbulence

– Indoor pets, plants, etc.

Sampling methods

‘Non-culturable’ (air) • spore traps

Culturable (air) • Anderson,

biocassettes

Direct microscopic examination (qualitative) • Tape, swab, bulk

Non-culturable Fungi Air Sampling

Spore traps (e.g., air-o-cells)

Sampled fungi (viable/non-viable) are analyzed under

microscope

Used for determining total levels of fungi in air

• Can provide… – ID to genus level

– Concentration (spores/m3)

– Genus-level comparison between samples

EMLab P&K http://www.emlab.com/m/store/003-2022-01_Lg.jpg

Culturable Fungi Air Sampling

Andersen, biocassettes, RCS, etc.

Sampled fungi are collected onto growth media; subsequently

enumerated and isolated for ID

Used for determining species and viability of fungi in the air

• Can provide… – ID genus + species (e.g.,

Aspergillus, Penicillium)

– Concentration (CFU/m3)

– Species-level comparison between samples

EMLab P&K http://www.emlab.com/m/store/012-3347-00_Lg.jpg

Surface Sampling

Surface sampling (tape lift, bulk, swab)

Sampled fungi (viable/non-viable) are analyzed under

microscope

Used to verify presence /absence of mould on

surfaces

• Can provide… – relative level of mould on

a surface (qualitative, genus level)

– information on whether viable fragments or spores are present

– information on background debris

Interpreting Results – Compare Indoor vs. Outdoor (control)

Anaylze lab results… • ‘Expected’ moulds

and levels between… – Suspect areas…

• indoor air • surfaces

– ‘Control’/baseline areas… • outdoor air • non-suspect areas/rooms

• Any potential indicators of indoor mould/dampness? – further investigation?

Interpreting Results – Potential indicators

• spores/m3, CFU/m3, # hyphal fragments/m3: Indoor > outdoor

Level

• Mould (genus/species) ID’ed in indoor sample are dissimilar to those in outdoor sample

• presence of a genus/species in indoor but NOT outdoor sample

Diversity

• mould that are dominant in indoor sample are dissimilar to those in outdoor sample

Dominance

Interpreting Results – Potential indicators

These are not commonly found in indoor air:

Rusts, smuts (plant pathogens/fungi)

Pollen, insect parts

Hydrophilic fungi

• Typical hydrophilic fungi – Stachybotrys – Fusarium – Chaetomium – Trichoderma – Ulocladium – Alternaria – Acremonium – Actinomycetes – Epicoccum – Rhizopus…

World Health Organization. WHO guidelines for indoor air quality: Dampness and mould. Copenhagen, Denmark: WHO, Regional Office for Europe; 2009. Available from: http://www.euro.who.int/document/E92645.pdf

Interpreting Results

• Aspergillus fumigatus, A. versicolor, A. niger

• Penicillium chrysogenum • Fusarium • Stachybotrys • Trichoderma • Chaetomium…

Toxigenic/Pathogenic mould

• Presence in multiple

indoor air samples may support the need for further investigation or remediation

Let’s look at some example lab reports and briefly go over them

• Non-culturable air • Culturable air

• Surface

Interpreting Results

• Results should not be interpreted in isolation. – Needs qualitative risk assessment

• Information gathering + building history » Complainants, tenants, employees, OHS, managers,

maintenance staff (building, custodial, engineer)

• Visual/Field inspection for mould growth and dampness • Professional judgement (may involve a team) • Assessment and remediation needs to consider

individual site-specific conditions and objectives

Interpreting Results • Consider:

– Adequacy of other information to assess for mould growth and dampness

• What is the need for and reasons for sampling?

– Sampling method and protocol • What are the pros, cons, limitations?

– Objective of sampling • What will be the use of lab results?

• Do results indicate need for further investigation, remediation, etc.?

• Testing cannot tell you whether human health effects will occur.

Interpreting Results

• Visible mould or dampness is ‘unacceptable’ from hygiene perspective – sample only if visual inspection unclear or suspect

hidden mould (e.g., in crawlspaces)

• If sampling results indicate hidden mould… – Is there a reasonable exposure pathway?

Management

Education

• Inform on… – health effects – vulnerable populations – potential need for professional

assessment/remediation – preventing moisture/mould issues

Remediation

• Many resources and guidelines available – see additional resources

Mould Resources

NCCEH Evidence Reviews: • Palaty C, Shum M. Health effects from mould exposure in indoor environments.

Vancouver, BC National Collaborating Centre for Environmental Health; 2012 Jul. Available from: http://www.ncceh.ca/en/practice_policy/ncceh_reviews/mould_and_health_effects

• Palaty C. Mould assessment recommendations. Vancouver, BC: National Collaborating Centre for Environmental Health; 2010 Oct. Available from: http://www.ncceh.ca/en/practice_policy/ncceh_reviews/mould_assessment.

• Palaty C. Mould remediation recommendations. Vancouver, BC: National Collaborating Centre for Environmental Health; 2010 Oct. Available from: http://www.ncceh.ca/en/practice_policy/ncceh_reviews/mould_remediation.

EMLab P&K

• Sampling Overview • http://www.emlab.com/s/sampling/S

ampling.html

• Sample lab reports • http://www.emlab.com/app/services/

Services.po?c=1

• An index of some commonly encountered fungal genera • http://www.emlab.com/app/fungi/Fun

gi.po

• Glossary • http://www.emlab.com/s/sampling/F

ungalGlossary.html

Mold & Bacteria Consulting Laboratories (MBL)

• Results Interpretation

• http://www.moldbacteria.com/category/results-interpretation

Guidelines • Health Canada. Fungal contamination in public buildings: A guide to recognition and management.

Ottawa, ON: Health Canada, Environmental and Workplace Health; 1995. Available from: http://individual.utoronto.ca/jscott/fpwgmaqpb001.pdf.

• Health Canada. Fungal contamination in public buildings: Health effects and investigation methods. Ottawa, ON: Health Canada, Environmental and Workplace Health; 2004. Available from: http://www.hc-sc.gc.ca/ewh-semt/pubs/air/fungal-fongique/index-eng.php.

• Health Canada. Residential indoor air quality guidelines - Moulds. Ottawa, ON: Health Canada, Environmental and Workplace Health; 2007 Available from: http://www.hc-sc.gc.ca/ewh-semt/pubs/air/mould-moisissure-eng.php.

• New York City Department of Health and Mental Hygiene. Guidelines on assessment and remediation of fungi in indoor environments. New York, NY: Environmental and Occupational Disease Epidemiology Unit; 2008 Nov. Available from: http://www.nyc.gov/html/doh/downloads/pdf/epi/epi-mold-guidelines.pdf.

• World Health Organization. WHO guidelines for indoor air quality: Dampness and mould. Copenhagen, Denmark: WHO, Regional Office for Europe; 2009. Available from: http://www.euro.who.int/document/E92645.pdf

Books

• Flannigan B, Samson RA, Miller JD, editors. Microorganisms in Home and Indoor Work Environments. 1 ed: CRC Press; 2002.

• Flannigan B, Samson RA, Miller JD, editors. Microorganisms in Home and Indoor Work Environments. 2 ed: CRC Press; 2011.